Webpage: https://www.invisalign.com.hk
Device: Desktop Computer
Region: United States West (Oregon)
Single Region Score
ARIA dialog elements without accessible names may prevent screen readers users from discerning the purpose of these elements. [Learn how to make ARIA dialog elements more accessible].
Third party code can significantly impact load performance. [Reduce and defer loading of third party code] to prioritize your page's content.
Optimize LCP by making the LCP image [discoverable] from the HTML immediately, and [avoiding lazy-loading]
Low-contrast text is difficult or impossible for many users to read. [Learn how to provide sufficient color contrast].
Resources are blocking the first paint of your page. Consider delivering critical JS/CSS inline and deferring all non-critical JS/styles. [Learn how to eliminate render-blocking resources].
Search engines may use `href` attributes on links to crawl websites. Ensure that the `href` attribute of anchor elements links to an appropriate destination, so more pages of the site can be discovered. [Learn how to make links crawlable]
Serve images that are appropriately-sized to save cellular data and improve load time. [Learn how to size images].
Layout shifts occur when elements move absent any user interaction. [Investigate the causes of layout shifts], such as elements being added, removed, or their fonts changing as the page loads.
Image formats like WebP and AVIF often provide better compression than PNG or JPEG, which means faster downloads and less data consumption. [Learn more about modern image formats].
These are the largest layout shifts observed on the page. Each table item represents a single layout shift, and shows the element that shifted the most. Below each item are possible root causes that led to the layout shift. Some of these layout shifts may not be included in the CLS metric value due to [windowing]. [Learn how to improve CLS]
Keep the server response time for the main document short because all other requests depend on it. [Learn more about the Time to First Byte metric].
This is the largest contentful element painted within the viewport. [Learn more about the Largest Contentful Paint element]
Reduce unused rules from stylesheets and defer CSS not used for above-the-fold content to decrease bytes consumed by network activity. [Learn how to reduce unused CSS].
Image display dimensions should match natural aspect ratio. [Learn more about image aspect ratio].
Source maps translate minified code to the original source code. This helps developers debug in production. In addition, Lighthouse is able to provide further insights. Consider deploying source maps to take advantage of these benefits. [Learn more about source maps].
Consider lazy-loading offscreen and hidden images after all critical resources have finished loading to lower time to interactive. [Learn how to defer offscreen images].
Consider reducing the time spent parsing, compiling and executing JS. You may find delivering smaller JS payloads helps with this. [Learn how to minimize main-thread work]
Your first network request is the most important. Reduce its latency by avoiding redirects, ensuring a fast server response, and enabling text compression.